Bowel disorders are often characterized by bloating and constipation and are thought to affect at least 20% of the population. Yet, to date no effective therapy is available. Such bowel disorders include irritable bowel syndrome (IBS), functional constipation, chronic pseudo-obstruction, and chronic abdominal bloating syndrome. Symptoms include abdominal pain, constipation, bloating, acid reflux, flatulence, nausea and vomiting, chronic lethargy and sleep disorders.
IBS is a gastrointestinal disorder characterized by chronic abdominal pain and altered bowel habits with either constipation (IBS-C), diarrhea (IBS-D) or both (IBS-M; mixed type). IBS is the most commonly diagnosed GI condition. It is second only to the common cold as a cause of absence from work. It is estimated that around 20% of the general population suffers from IBS, resulting in increased health care costs. Annual direct and indirect costs are reported to be of up to $30 billion.
Functional constipation is the most common gastrointestinal complaint affecting the 63 million Americans with IBS. IBS is often characterized by hard stools or straining or having fewer than 3 bowel movements a week at least 25 percent of the time.
Despite the seriousness of IBS as a health care issue the underlying causes remain largely unknown. The traditional focus has been on alterations in the GI motility and on visceral hypersensitivity. Recent reports suggest that small intestinal bacterial overgrowth (SIBO) may play a significant role in the development of IBS, as well as obesity and type II diabetes. For example, multiple studies have demonstrated excessive coliform bacteria in the small intestines of IBS patients.
Methanogenic archaebacteria are an important group of gut colonizing bacteria contributing to SIBO that grow primarily under anaerobic conditions and produce methane (CH4) as a by-product of fermentation. The degradation of carbohydrates by enteric bacteria, including methanogenic bacteria, leads to the production of short chain fatty acids (butyrate, propionate, acetate), as well as carbon dioxide, hydrogen and methane. These products are associated with acidic stools, abdominal distension, flatulence, diarrhea, and constipation. Methanogenic bacteria are unique, in that their metabolism increases in the presence of products from other bacteria. They use hydrogen and ammonia from other bacteria as substrates for the production of methane. Intestinal methane production has been linked to IBS-C, functional constipation, obesity and type II diabetes. The methane directly influences the colonic transit time, colonic motility, and rectal sensorimotor function resulting in lowered pain threshold.
There is growing evidence that the microbiota plays a critical role in the determinant of nutrient uptake, energy regulation and ultimately weight and metabolic disorders. Gut microbes can influence both the harvest of energy from components of the diet and how energy is stored and expended. In this regard, methane-producing bacteria have been found to be present in greater abundance in obese mice and humans compared with lean animals and individuals. It has been shown that hydrogen transfer between bacterial and archaeal species may increase energy uptake by the large intestine via methanogens by removing fermentation intermediates, such as H2 or formate. This allows greater production and availability of short chain fatty acids for absorption across the intestinal lumen. The methane produced also acts as a local paralytic allowing food substrates to have longer contact with the absorptive villi in the small bowel.
Treatment options for gastrointestinal disorders and obesity are limited. For example, although there are treatment options for IBS including the use of bulking agents, such as fiber, antispasmodics, antidepressants, and more recently probiotics and antibiotics, such treatment options are not sufficiently effective and do not treat the underlying problem. For example, bulking agents have not been shown to demonstrate an improvement in global IBS symptoms and actually have been shown to increase bloating and pain. Anti-spasmodics available in the US for IBS include dicyclomine, hyoscyamine, and peppermint oil. A recent meta-analysis found only peppermint oil to be effective in improving global IBS symptoms. Antidepressants have shown poor and conflicting results, ultimately demonstrating no relief in symptoms. Regarding probiotics, a large meta-analysis demonstrated no superior effect over placebo. And, of course, obesity is an epidemic problem with few effective options.
Surveys have demonstrated that less than 14% of patients with IBS are satisfied with their treatment. Presently, there are few dependable pharmaceutical treatment options for IBS or obesity.
In view of the current shortcomings associated with bowel disorder treatments, including IBS and functional constipation, as well as obesity or undesired weight gain, there is a need for new treatments. The present application addresses this need and provides new methods and formulations for treating such disorders or diseases.